Home Postcode finder SA Monarto Monarto postcode SA Monarto is a locality in South Australia covered by postcode 5254. Postcode 5254 State or territory South Australia (SA) Region Sa Subs Near 2 Add a free Monarto business listing Be the first listing in Monarto Common questionsWhat is the postcode for Monarto?Monarto, SA has the postcode 5254.What state is Monarto in?Monarto is in South Australia (SA).Does postcode 5254 cover more than one suburb?Yes. Postcode 5254 covers 12 localities, so the postcode alone does not identify Monarto. Browse other postcodes in South Australia, or widen the search to every Australian postcode.